The dimensions of the zones are mostly determined by a building s length and width.
Mean roof height asce 7.
Np gravel and stone not permitted for any roof height.
For intermediate values of vasd the height associated with the next higher value of vasd shall be used or direct interpolation is permitted.
See help glossary link above for explanation.
Asce 7 16 added another zone and it presents the potential to have four roof zones.
Asce 7 05 and asce 7 10 have three roof zones.
A simplified procedure and an analytical procedure.
Asce 7 10 provides two methods for wind load calculation.
Asce 7 16 wind velocity to pressure hover click labels see help images at bottom.
The wind speeds correspond to 3 second gust speeds at 33 ft above ground for exposure c category.
Pressure increases vary by zone and roof slope.
For si 1 foot 304 8 mm.
Mean roof height asce 7 per asce 7 the mean roof height h is defined as the average of the roof eave height and the height to the highest point on the roof surface except that for roof angles of less than or equal to 10 the mean roof height is permitted to be taken as the roof eave height.
Mean roof height mrh ft this is needed to determine canopy pressure.
Figure asce 7 95 external pressure coefficients gcp for loads on building components and cladding for enclosed or partially enclosed buildings with mean roof height h less than or equal to 60 ft 18 m.
This table compares results between asce 7 10 and asce 7 16 based on 140 mph wind speeds in exposure c using the smallest ewa at 15 foot mean roof height in zone 2.
Interior field perimeter and corner see figure 3.
1 mile per hour 0 447 m s.
Mean eave height ft select yes if within 90 of height at.
Asce 7 16 also.
This is the average roof height of the main residence from the peak to the eave.
Field perimeter and corner see figure 2.
Figure asce 7 95 walls figure asce 7 95 walls.
The simplified procedure is for building with a simple diaphragm roof slope less than 10 degrees mean roof height less than 30 feet 9 meters regular shape rigid building no expansion joints flat terrain and not subjected to special wind condition.
In some cases not shown in table 1 such as for zone 1 the revised coefficients produce an approximate doubling of roof pressures.
Visually aama tir a15 14 illustrates the mean roof height as per the image below where h on the sloped roof is ridge height eave height 2.
These changes affect how you determine wind uplift resistance.
Explanation of asce 7 05 asce 7 10 and asce 7 16.
